ATI Crossfire Compatibility Chart

[CrackerJack]

Hope this helps some way or another!



They moved the 2900's to Q3

I know some have heard me say this a thousand times. But I ready to unleash the cards with some new drivers . And ATI just told me a few weeks that it is supported for crossfire :shadedshu

 

[GSG-9]

I just assumed i could not crossfire my 2900 and 4870, Wish I had not sold 2900 now..

 

[CrackerJack]

I just assumed i could not crossfire my 2900 and 4870, Wish I had not sold 2900 now..

You can't crossfire 2900 and 4870

 

[imperialreign]

suppsedly, though, the HD3000 and HD4000 series will crossfire; but I've heard performance is absolutely bunk . . .

I'd still like to see more backwards compatible Hybrid Crossfire support . . . I'd love to be able to rig up my two RV570s to these RV670s

 

[SystemViper]

could you use the 3870X2 with the 4000 series or the 2900xt series?

Regards
steve

 

[GSG-9]

could you use the 3870X2 with the 4000 series or the 2900xt series?

Regards
steve

I read it as a yes for the 2900Pro and 4000 series but they said you cant above. I think I just dont understand the chart..

 

[SystemViper]

I think I just dont understand the chart..

I always thought that all the ati cards could crossfire with any ati card, that chart has me confuzed.

I have a 3870X2

I also have 2 - 2900xt's But could i get a 4870 and use it with a 3870x2 or the 2900xt????

 

[muon]

Whats there to be confused about? Only the red box combinations can be crossfired. Read both axes.

 

[GSG-9]

Whats there to be confused about? Only the red box combinations can be crossfired. Read both axes.

Well the fact people crossfired the 3 series with the 4 series and according to the chart above you cant, so im supposed to trust the above chart that i cant crossfire a 2900 with a 3 or 4 series?

Im not talking about performance, just the ability to.

 

[Megasty]

You can always CF a 3000 series card with a 4000 series card, but that doesn't mean it will work. It won't. The performance you'll get will be based off the card in the 1st slot.
You can also CF a 2000 series with a 3000 series with minimal sucess. But there a definite performance increase when I tried to CF a 3870 & a 2900XT.

 

[muon]

No one has crossfired 38xx and 48xx cards yet as far as I know, unless you can show me where. I looked pretty extensively when I had both cards.

 

[GSG-9]

Once again I was not talking about performance, just the ability of the hardware to do it.

No one has crossfired 38xx and 48xx cards yet as far as I know, unless you can show me where. I looked pretty extensively when I had both cards.

edited for a missread
There are fNo one has crossfired 38xx and 48xx cards yet as far as I know, unless you can show me where. I looked pretty extensively when I had both cards.[/QUOTE]"]ourm threads online about doing it (2nd link)

 

[muon]

Once again I was not talking about performance, just the ability of the hardware to do it.

Of course you can run 2 card on a single board and using them individually. Nothing's stopping that, but whats the point of creating a chart for that? This is clearly about actual crossfire which is entirely different.

Crossfire isnt about running 2 cards on a board but using both to combine performance. Thats why you can disable crossfire via CCC, just because you ahve both cards in your board doesnt mean they are in crossfire.

For example, its possible to run a geforce 4 and 8800gts together. Is there any hope of them being in SLI? No of course not.

edit: need to fix your link

Also, I dont believe Megasty. It must have been something else which led to the performance increase. the drivers simply dont support it.

 

[GSG-9]

Of course you can run 2 card on a single board and using them individually. Nothing's stopping that, but whats the point of creating a chart for that? This is clearly about actual crossfire which is entirely different.

Crossfire isnt about running 2 cards on a board but using both to combine performance. Thats why you can disable crossfire via CCC, just because you ahve both cards in your board doesnt mean they are in crossfire.

If they are not in crossfire though only one of the cards is used for rendering (my understanding) by combining a HD2 series with a HD4 series you are effectively tying a fast runner to a kid in a wheelchair and telling them to run a 3 legged race.
I have a worklog of my rig (htpc+watercooling as of now) and i wanted to implement crossfire or sli, it would be doing it because it can be done. Im not made out of cash and cannot afford to buy a 2nd card right now, I could have afforeded to keep my 2900 if i was sure I could crossfire it for the project.

 

[Megasty]

But why would you want to CF something like a 4870 & a 3870. The 4870 ia more than twice as fast as a 3870. Plus the 4870 can handle anything by itself. It would only make sense that the difference in their performance would disturb the communication. The difference in performance of the 4870 & 4850 doesn't need to take this into account since both GPUs are the same, despite the clock difference.

EDIT: Grr GSG-9, the way you word it is amazing

Of course you can run 2 card on a single board and using them individually. Nothing's stopping that, but whats the point of creating a chart for that? This is clearly about actual crossfire which is entirely different.

Crossfire isnt about running 2 cards on a board but using both to combine performance. Thats why you can disable crossfire via CCC, just because you ahve both cards in your board doesnt mean they are in crossfire.

For example, its possible to run a geforce 4 and 8800gts together. Is there any hope of them being in SLI? No of course not.

edit: need to fix your link

Also, dont believe Megasty. It must have been something else which led to the performance increase. the drivers simply dont support it.

Did you even read my post, I said it wouldn't work for the 4x & 3x But the increase with the 2900xt & 3870 was 10 fps at the most.

 

[muon]

Simply put. Your definition of crossfire means that crossfire predates its actual release with x8xx cards. Also, your analogy is completely wrong for crossfirex.

Did you even read my post, I said it wouldn't work for the 4x & 3x But the increase with the 2900xt & 3870 was 10 fps at the most.

Okay sorry. I didnt see that you said 2900xt. Yeh thats probably possible since the 38xx and 2900xt are almost the same. I think I remember the possibility being floated around when the 38xx cards came out.

 

[GSG-9]

Simply put. Your definition of crossfire means that crossfire predates its actual release with x8xx cards. Also, your analogy is completely wrong for crossfirex.

Is it? completely wrong? I would be very grateful if you would enlighten me on what and how crossfire actually works then ghost. Because I don't seem to know then.

 

[muon]

Is it? completely wrong? I would be very grateful if you would enlighten me on what and how crossfire actually works then ghost. Because I don't seem to know then.

Well each card simply renders a frame alternately as part of the same sequence. Using 2 cards without crossfire allows you to render 2 indpendent sequences i.e. monitors. But you cant combine performance.

You can use both a h2k and hd4k card on the same board but youll only be able to do the latter. Or thats what I think. As far as I know thats correct. This has been possible for ages before crossfirex.

The second point is, crossfirex shouldnt impede the performance of the better card. It doesnt have to downclock like the original version of crossfire did. So its not a 3 legged race as such.

 

[GSG-9]

The second point is, crossfirex shouldnt impede the performance of the better card. It doesn't have to downclock like the original version of crossfire did. So its not a 3 legged race as such.

Its my understanding cards used in crossfire x must have the same amount of memory or it cuts out the excess ram of the faster card. (Not really impotent I just remember being told that)

It may not drop to the clocks of the lower card like it did in the past, but it still bottlenecks from the lower card I am sure, The 4870 will render twice as many frames as a 3870 in the same time, if crossfirex renders half the workload to each card that would cause the 4870 to wait for the 3870 every other frame. That sounds like a three legged race to me...

 

[Megasty]

OK, there was originally 4 options availible for CF. Today we've basically melted all of those options into AFR. Scissor was also used with SLI where 1 card rendered 1 half the screen & the other did the other half. Then there was super tiling where the screen was rendered like a checker board, 1 card rendered the red tiles & the other did the black. Lastly there was super AA, its the same super AA we know today that didn't improve performance but only image quality.

Scissor & super tiling basically died off when AFR proved to be faster than both & that also led the way for 3 & 4 GPU applications. AFR only works when the GPUs are in the same league. That's why the 2900xt & 3870 could be done, but the RV770 obliterates the RV670 so it will never happen.

 

[CrackerJack]

Yeah I agree with Megasty, why would you crossfire say a 3870/4870. I could see maybe, 3870/4850 or 3870x2/4850. But from the last i heard there's no crossfire with 3k and 4k series cards. But i've only heard that crossfire works with 2k and 3k series cards. But there's not big increase, since it's using the lower spec card.